NTT DOCOMO Activities in 5G Field Trials

Yukihiko Okumura
Satoshi Suyama
Jun Mashino

5G Laboratories
NTT DOCOMO, INC.

From the left: J un Mashino, Yukihiko Okumura,
Satoshi Suyama

1.Introduction
In addition to featuring higher capacity and transmission
speed, 5th generation mobile communication systems (5G) willfeature massive connectivity and ultra-reliable and low-latency
communication. These features are also highly anticipated forwhen commercial services begin in 2020. NTT DOCOMO has
been a primary implementer of the FY2017 Ministry of Internal
Affairs and Communications (MIC) initiative, “Study of technicalrequirements for 5th generation mobile communication systems,
which will enable ultra-high-speed communication exceeding
10 Gbps in densely populated areas” (study group one (GI)).
This article gives an overview of this study and introduces someexamples of trials in related application areas.

2. Trial Overview

the areas of entertainment, smart-city/smart-area, and medicine,in collaboration with partner enterprises (see Table). These casestudies are introduced below.

3. 5G field trials in the entertainment area
3.1 Entertainment system using VR/MRIn December 2017, we conducted a trial of a VR
entertainment system which captured video using a 4K highdefinition 360° live camera at Tokyo Skytree Town®, which
was then transmitted using 5G to a 220° wide viewing angle
head-mounted display for viewing (Figure 1). Stable delivery
was achieved using a variable-rate video encoder implemented
on the distribution server, compressing the video according to
the state of communications for each user, from one minute to
the next. During the same period, a 5G connection was madefrom inside the observation deck of Tokyo Skytree® (340 mThe concrete 5G field trials being conducted by the Ministryof Internal Affairs and Communications (MIC)in various application fields are proceeding with a ■ Table: Organizations participating in GI and their roles
3-year plan starting in FY2018, keeping in mind
the implementation of 5G in society, building
an open environment in which enterprises anduniversities from around the world can participate,
and working toward a world-leading introduction of5G in Japan. As part of this, NTT DOCOMO has
conducted studies to understand radio propagation
characteristics and evaluate 5G performance forultra-high-speed transmission using the 3.6-4.2
GHz, 4.4-4.9 GHz and 27.5-29.5 GHz bands.
These were done in densely-populated urban
environments with user terminals travelling at speeds
up to 30 km/h, so that 5G can be introduced using
these frequency bands. We observed throughputsof up to 10.2 Gbps with two users, both connectedin an outdoor environment at Tokyo SkytreeTown®, and this confirmed that ultra-high-speed
and high-capacity communication can be achievedin the field. Besides the radio transmission trial,
the study group GI evaluated radio propagation
cha racter ist ics, per for med simu lat ions oftransmission characteristics, and conducted trials
to check the feasibility of various 5G services inNew Breeze Autumn 20183

■ Figure 1: Entertainment system for trials

above the ground) to the roof of Asakusa train station EKIMISE
building, for a trial of a new communication style using mixedreality (MR) technology. For the trial, video of people inside theAsakusa station building (Figure 3) was transmitted at speeds
up to 4.5 Gbps, even at the transmission distance of 1.2 km,
successfully reproducing the people from the remote location on a
3D holographic video display.

4.1 Facility monitoring
In November 2017 at the National Museum of Emerging
Science and Innovation (“Miraikan”), we conducted a trial of a
new security system for inside facilities, using high definition
surveillance camera video and face-recognition access gates. The
information needed to implement security for specified areas isrecognized in images obtained using the surveillance cameras
in real time, using image recognition technology involving facecomparison and AI. We confirmed the ability to increase thefrequency of face checks by a factor of six with 5G, compared withusing 4G.

3.2 Trials at Tokyo Skytree Town®
In March 2018, we built indoor and outdoor test environments
in Tokyo Skytree Town® and Tokyo Soramachi®, and verified thefeasibility of services using 5G in a densely populated commercial
facility (Figure 2). In one trial, 8K multi-channel video was
4.2 Wide-area monitoringtransmitted using 5G, confirming the ability to receive stable
In March 2018, we conducted a trial of wide-area monitoring
video quality after forward error correction on both the radio
using a 4K high-definition camera mounted on the observation
access (physical) layer and the video (application) layer. In a digitaldeck of Tokyo Skytree® and an AI processing server. We analyzed
signage trial using ultra-low-power reflective displays, four tiled
the video from the wide-area camera to recognize vehicles driving
reflective displays were installed outdoors, and 4K video content
on highways, areas of congestion potentially caused by traffic
simulating advertising was sequentially transmitted
to them from a base station and displayed. This trial ■ Figure 2: Trials at Tokyo Skytree Townconfirmed that the content could be reproduced in
outdoor light without loss of image quality, and withgood contrast, and color reproduction. In a trial of video
transmission in an indoor environment modeled after acommercial facility, 5G ultra-high-density distributed
antennas were deployed, transmitting 4K HD video
to a mobile terminal, with several pedestrians walking
around the terminal. This trial confirmed that stabletransmission of video was possible, even when entering
tenants having complex premises.

4. 5G field trials in the smart city area
We conducted a trial of a new security model forurban spaces needed in smart cities, toward realizationof advanced security services that can handle crimes thatcurrent preventative measures cannot, such as crimes ofconviction (terrorism, random attacks, child predation,etc.). The trial used HD video, AI, and 5G to capture
predictors of crime so they can be prevented before theyoccur (Figure 3).

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New Breeze Autumn 2018

■ Figure 3: T rials of security in facility and urban spaces■ Figure 4: Trials of remote medical examinations

accidents, fires and other phenomena. The results showed thatthe ability to distinguish distant objects was clearly superior whenusing the relatively higher-resolution video transmittable using
5G, compared with 4G.

5. 5G field trials in the medical area
We conducted a trial of an advanced remote medical
examination service, providing improved medical examinations
in rural and mountainous areas, comparable to those available inurban general hospitals (Figure 5). We connected the Wakayama
Medical University Community Medical Support Center(Wakayama City) and the Japan National Health Insurance
Kawakami Clinic (Hidakagawa Town, Wakayama Prefecture)by network including 5G. We then introduced capabilities totransmit video from a 4K high-definition close-up camera used for
diagnosis of conditions of the skin, dental/oral, and other external
injury, and from other equipment used for internal examinations,such as ultrasonic imaging (echograms), and also a 4K highdefinition video conferencing system for medical interviews andconsultations between doctors.
In February 2018, we conducted a trial following the medical
treatment of patients for five cases (three dermatology, one plastic
surgery, and one cardiology case). Impressions from the doctors
and patients participating in this trial are described below.

5.1 Doctor impressions
・ Using the 4K camera capabilities and ability to examine
closely, I was able to see the external trauma well andperform the examination, which was not possibleusing earlier video conferencing systems. Wonderful!
(Dermatologist).
・ The 4K video was clear and of quality in no way inferior
to the images when using the echogram directly. I lookforward to using it to improve medical treatment inregional communities (Cardiologist).
・ The feeling that specialists can be present immediately isreassuring. This should be very effective in improving care
at clinics, and especially as an educational tool for young
doctors. (Clinic doctor).
5.2 Patient impressions・ With the doctor from the Medical University on thelarge screen, I was able to receive the medical examination
exactly as if I was there as an outpatient.
・ This time, I used this remote medical examination to geta second opinion. I had the examination through a screenthat gave a strong sense of presence, and received excellent
findings and new treatment methods as I would expectfrom a specialist at the general hospital. It was a real eyeopener!

New Breeze Autumn 20185